Delta Air Lines has taken significant steps toward introducing its elite airline fliers to the convenience and privacy of business jets. The carrier will now offer a business jet upgrade program for its “Medallion” frequent fliers (those who fly more than 25,000 miles annually on the airline).

The airspace between traditional business jet access models (charter, fractional ownership and jet cards) and first-class airline travel has been active lately, even if there’s not much to show for it. But while some would-be per-seat charter providers and fledgling “flight club” programs appear to be in a holding pattern, one alternative operator in California has quickly taken off: Surf Air, which offers more than a dozen scheduled daily flights between off-the-hub airports in the Bay Area and Los Angeles.

Hopscotch Air, a small charter operator that uses five-seat single-engine Cirrus light airplanes, just celebrated its fifth anniversary, a notable accomplishment in this economy. The company—which focuses on short flights, primarily within a 300-mile radius of New York City—serves destinations throughout New England and as far south and west as Washington, D.C., and most of Ohio.

You may never charter a business jet that requires a flight attendant. No chartered aircraft with 19 or fewer passenger seats needs one, according to U.S Federal Aviation Administration and European Aviation Safety Agency regulations.

A quality air charter provider should be able to have you in the air within two hours of receiving a call for a pop-up, or last-minute, domestic flight. [See “Taking Off in a Hurry”] But what if you need to alter the passenger manifest or amend your destination shortly before takeoff?

Trip-protection insurance is popular with airline passengers who worry that a change in plans could mean forfeiture of airfare, prepaid accommodations and other upfront travel costs. Many air charter customers could benefit even more from such coverage, due to the amount of money at stake. Charter operators typically assess cancellation penalties that escalate as departure times approach.

Perhaps you own a business jet and have been thinking about making it available for charter. That’s not always a great idea (see below) but if it makes sense for you, it can offer a rather painless way to recoup some operating costs. Here’s how to proceed.